KR20010019539A - Transmission Method for Packet data using Common Packet Channel - Google Patents

Abstract

PURPOSE: A method for transmitting packet data using a common packet channel is provided to make a user transmit supplementary information on packet data when initializing closed loop power control to a BS(Base Station), so as to enable the BS to promptly detect a use state of a CPCH(Common Packet CHannel) and allocate the CPCH to many users. CONSTITUTION: A user requests the allocation of a CPCH(Common Packet CHannel) to a BS(Base Station). Supplementary information on a length of packet data and a coding system is transmitted to the BS, when initializing power control of the allocated CPCH is performed. The packet data are transmitted to the BS through the allocated CPCH. The supplementary information is transmitted to the BS, by being mapped to one of a data field and a TFCI(Transport Format Combination Indicator) field of PC(Power Control)-preamble. If the supplementary information is mapped to the data field of the PC-preamble, a CPCH data coding system is used. And if the supplementary information is mapped to the TFCI field of the PC-preamble, a TFCI coding system is used.

Description

Transmission Method for Packet Data Using Common Packet Channel}

The present invention relates to the next generation mobile communication, and more particularly, to a packet data transmission method using a common packet channel, which is suitable for transmitting additional information of packet data to a base station through a common packet channel (CPCH) at a user side (UE). .

Recently, the ARIB and TTC in Japan, the ETSI in Europe, the T1 in the US, and the TTA in Korea have recently introduced the Third Generation Partnership Project (hereinafter abbreviated as 3GPP) to establish technical standards for next-generation mobile communication systems. Configured.

In the research section of the 3GPP research on the global radio access network (UTRAN) describes the definition and description of the transport channel (Physical channel) and the physical channel (Physical channel). The common packet channel (CPCH), which is one of the transmission channels, is used to transmit relatively long data to the base station BS through the up-link (UL) on the user side (UE). It is allocated between user side (UE).

In this case, the common packet channel (CPCH) is associated with a dedicated channel (DCH), which is a channel for performing closed loop power control on the common packet channel (CPCH) of the uplink (UP), and the dedicated channel (DCH) Is mapped to a dedicated physical control channel (DPCCH) which is a physical channel.

The common packet channel (CPCH) uses a random access scheme to provide communication services to multiple users (UEs). Accordingly, the network side UTRAN including the base station BS allocates a common packet channel (CPCH) that can be used to the user side (UE) that transmits packet data in a random access method as contention.

Hereinafter, a packet data transmission procedure using a common packet channel (CPCH) will be described in more detail according to a technology proposed by 3GPP (3GPP TSGR1 # 5 (99) 592 Golden Bridge Technology, “CPCH Physical Layer Procedures”).

1 is a view showing the overall structure of a conventional common packet channel (CPCH), Figure 2 is a flow chart showing a packet data transmission procedure using a conventional common packet channel.

1 and 2, a common packet channel (CPCH) is functionally divided into four parts, and accordingly, a packet data transmission procedure using a common packet channel may be divided into four parts.

The first is a power ramping process, in which the base station BS adjusts the level of signal transmission power so that the base station BS can receive a signal (S200).

The power ramping process includes an access preamble (hereinafter, abbreviated as AP) transmitted from a user side (UE), and an access preamble acquisition indication channel, which is a base station (BS) response signal to the AP. , Hereinafter abbreviated as AP-AICH). In this case, the AP is composed of 16 symbol groups and spreading codes, and the AP-AICH is composed of 16 symbol groups, spreading codes, and channelization codes.

The second is a collision detection and processing process of the common packet channel (CPCH) that is performed by requesting the allocation of the same common packet channel at the same time on multiple user side (UE) (S201).

The collision detection and processing of the common packet channel (CPCH) is performed by a collision detection preamble (hereinafter abbreviated as CD-P) transmitted from a user side (UE), and a base station (BS) response to the CD-P. It consists of a signal CD-AICH. In this case, like the AP and the AICH, the CD-P is composed of 16 symbol groups and spreading codes, and the CD-AICH is composed of 16 symbol groups, spreading codes, and channelization codes. As described above, the symbol groups of the AP, AP-AICH, CD-P, and CD-AICH are all 16, and each symbol group corresponds one-to-one with 16 CPCH channelization codes.

The third is a Close Loop Power Control (CL-PC) initialization process of a common packet channel (CPCH) allocated to the UE. The UE and the BS are uplinked to each other. link, UP), and a downlink (down-link, DL) for transmitting a CL-PC preamble (S202).

Here, the CL-PC preamble includes a pilot field for estimating a channel state as shown in FIG. 3, a TPC field and a dummy data field for the CL-PC. In the uplink, dummy data is transmitted through a dedicated physical data channel (DPDCH) of I stage, and pilot data and TPC data are transmitted through a dedicated physical control channel (DPCCH) of Q stage. At this time, in the downlink, the dedicated physical control channel (DPCCH) and the dedicated physical data channel (DPDCH) are time-divided to transmit pilot data, TPC data, and dummy data to the base station BS.

Fourth, a process of transmitting packet data from the UE to the BS is packet data through an uplink dedicated physical control channel (DPCCH) and a dedicated physical data channel (DPDCH). , The pilot data and the TPC data is transmitted to the base station (BS), the base station (BS) through the downlink dedicated physical control channel (DPCCH) to the pilot data and TPC data, which is control information for closed-loop power control (UE) It transmits to (S203).

However, considering the conventional packet data transmission procedure using the common common packet channel (CPCH), since the base station cannot know additional information such as length and coding scheme for the packet data transmitted on the uplink, the common packet channel can be efficiently determined. It cannot be assigned.

In more detail, the base station does not know in advance the end time of the common packet channel (CPCH) according to the length of the packet data, which is additional information on the packet data transmitted through the common packet channel, and the coding method of the packet data. When the common packet channel is terminated, the common packet channel cannot be allocated to a new user quickly, and the packet packet cannot be predicted when the end of transmission of the packet data can be predicted, and thus the common packet channel cannot be scheduled for another use. There is a problem that can not be operated.

Accordingly, an object of the present invention has been devised in view of the above-mentioned problems of the prior art, and it is possible to efficiently allocate a common packet channel by transmitting additional information of packet data transmitted through a common packet channel to a base station. It is to provide a packet data transmission method using a packet channel.

According to an aspect of the present invention for achieving the above object, the packet data transmission method using a common packet channel is a user-side (UE) is assigned by requesting the allocation of a common packet channel (CPCH) to the base station, and Transmitting additional information about the length and coding scheme of packet data to be transmitted upon power control initialization of an assigned common packet channel (CPCH); and transmitting the packet data through the assigned common packet channel (CPCH). The step of transmitting to the base station.

Preferably, the additional information is mapped to any one of a data field of a power control preamble (PC-Preamble) and a Transport Format Combination Indicator (TFCI) field to perform the power control, and is transmitted to the base station. When mapped to the data field of the power control preamble, a common packet channel (CPCH) data coding scheme is used. When the additional information is mapped to the TFCI field of the power control preamble, a TFCI coding scheme is used.

1 is a view showing the overall structure of a conventional common packet channel (CPCH).

2 is a flowchart illustrating a packet data transmission method using a common packet channel (CPCH) shown in FIG.

3 is a diagram illustrating a structure of a power control preamble of a conventional common packet channel (CPCH).

4 is a flowchart illustrating a packet data transmission method using a common packet channel (CPCH) according to the present invention.

5 illustrates a structure of a common packet channel (CPCH) according to the present invention.

6 illustrates the structure of a power control preamble according to a first embodiment of the present invention;

7 illustrates a structure of a power control preamble according to a second embodiment of the present invention.

Hereinafter, a configuration and an operation according to an exemplary embodiment of the present invention will be described with reference to the accompanying drawings.

The present invention proposes a packet data transmission method using a common packet channel for transmitting additional information on packet data to a base station when power control initialization of a common packet channel (CPCH) allocated by a user side (UE).

To this end, the present invention further configures a packet header transmission process for transmitting additional information about packet data to be transmitted in a packet data transmission procedure using a conventional common packet channel (CPCH).

In this case, the additional information of the packet data may be transmitted in various ways, but in the present invention, during the duration of the power control preamble using a power control preamble (PC-Preamble) transmitted on the uplink when the closed loop power control is initialized. Is transmitted to the base station (BS).

4 is a flowchart illustrating a packet data transmission procedure using a common packet channel (CPCH) according to the present invention.

Referring to FIG. 4, first, a UE performs a power ramping process (S401).

In the power ramping process, the UE (UE) monitors the AICH transmitted from the base station BS and checks whether there is a current common common channel (CPCH).

As a result of the check, if there is an empty common packet channel, the UE (UE) selects one of the empty common packet channels (CPCH) arbitrarily and then signifies one-to-one correspondence with the selected common packet channel (CPCH). The AP is transmitted to the base station (BS) by using. The UE increases the AP power at regular intervals until it receives the AP-AICH, which is a base station (BS) response signal for the transmitted AP.

Meanwhile, the base station (BS) receives each AP from several UEs, selects one AP to allocate a common packet channel (CPCH), and selects an AP-AICH using a signature used for the selected AP. Transmit to the user side (UE).

Then, each UE receives the AP-AICH and compares it with the AP transmitted by the UE to detect whether the UE is selected. At this time, the UE that is not selected starts the power ramping process from the beginning.

Next, collision detection and processing of a common packet channel are performed (S401).

That is, each user side (UE) receiving the AP-AICH composed of the same symbols as the AP transmitted from the base station BS selects one signature from a total of 16 symbol groups at random and selects the selected symbol. The CD-P is transmitted to the base station BS. Then, after receiving the CD-P transmitted from each UE (UE), the BS selects one of the transmitted CD-Ps randomly and selects the selected CD-P to prevent collision of the common packet channel (CPCH). The CD-AICH having the same signature as the S1 is transmitted.

Subsequently, an initialization process of closed loop power control is performed (S402).

That is, the user UE receiving the CD-AICH having the same signature from the base station BS transmits a power control preamble PC-Preamble to the base station BS, and the other user UE receives the CD-AICH. Restarts the power ramping process. At this time, the base station BS also transmits the power control preamble to the user side UE, similarly to the user side UE, to initialize closed loop power control.

Subsequently, a packet header transmission process according to the present invention is performed (S403).

In the packet header transmission process, the UE (UE) inserts length information and coding information of the packet data, which is additional information about the packet data to be transmitted, into the blank portion of the power control preamble and transmits the same to the base station BS. In this case, the additional information of the packet data inserted into the blank portion of the power control preamble may be selected by using either an uplink dedicated physical control channel (UL DPCCH) or an uplink dedicated physical data channel (UL DPDCH). ).

Subsequently, the UE transmits the packet data to the base station BS according to the packet data transmission process (S404). At this time, the UE transmits packet data, pilot data, and TPC data to the base station BS through a common packet channel (CPCH), and the base station UE downlinks the pilot data and TPC information for closed loop power control. Transmit to the user side (UE) through a dedicated physical control channel (DL DPCCH).

As described above, the additional information of the packet data is transmitted during the period of the uplink power control preamble (UL PC-Preamble) when the closed loop power control is initialized for the assigned common packet channel (CPCH) as shown in FIG. 5. do. Here, the additional information of the packet data is mapped to the blank portion of the power control preamble and transmitted to the base station (BS), and the present invention uses two mapping schemes.

First embodiment

The first embodiment describes a case in which additional information of packet data is mapped to a data field of an uplink power control preamble and transmitted to a base station BS through an uplink dedicated physical data channel UL DPDCH. .

6 is a diagram showing the structure of a power control preamble according to a first embodiment of the present invention.

Referring to FIG. 6, since the data field transmitted through the UL dedicated physical data channel (UL DPDCH) in the conventional uplink power control preamble is composed of dummy data which is meaningless, according to the present invention, the additional information of the packet data, that is, the packet The length information and the coding information of the data are mapped and inserted into the data field and then transmitted to the base station BS.

In this case, the additional information of the packet data is coded according to a common packet channel (CPCH) data encoding scheme, and the information encoded in the CPCH is mapped to the data field of the uplink power control preamble and transmitted to the base station BS. do.

Second embodiment

According to the second embodiment, additional information about packet data is mapped to a transport format combination indicator (TFCI) field of an uplink power control preamble and transmitted to a base station (BS) through an uplink dedicated physical control channel (UL DPCCH). Explain.

7 is a diagram showing the structure of a power control preamble according to a second embodiment of the present invention.

Referring to FIG. 7, a conventional uplink power control preamble transmitted through an uplink dedicated physical control channel (UL DPCCH) includes a pilot field and a TPC field, and the TFCI field configured in the pilot field is meaningless dummy data. In the present invention, additional information of the packet data, that is, length information and coding information of the packet data is mapped to the TFCI field and transmitted to the base station BS.

In this case, the additional information of the packet data is coded according to the TFCI encoding method, and the information encoded in the TFCI is mapped to the TFCI field of the uplink power control preamble and transmitted to the base station BS.

As described above, according to the packet data transmission method using the common packet channel according to the present invention, since the additional information about the packet data is transmitted to the base station when the closed loop power control is initiated by the user side, the base station uses the common packet channel (CPCH). The state can be quickly identified, and a common packet channel (CPCH) can be efficiently allocated to a plurality of users, and the common packet channel (CPCH) can be scheduled for another use.

In addition, the base station can preset the reception modem of the packet data by using the coding information of the packet data according to the additional information of the packet data, thereby reducing the time delay.

Claims (3)

Requesting assignment of a common packet channel (CPCH) to a base station by a user side (UE); Transmitting additional information regarding the length and coding scheme of packet data to be transmitted upon power control initialization of the assigned common packet channel (CPCH), to the base station; And transmitting the packet data to the base station through the assigned common packet channel (CPCH). The method of claim 1, wherein the transmitting of the additional information to the base station comprises: The additional information is mapped to any one of a data field of a power control preamble (PC-Preamble) and a Transport Format Combination Indicator (TFCI) field that performs the power control, and is transmitted to the base station. Packet data transmission method used. The method of claim 2, wherein when the additional information is mapped to a data field of the power control preamble, a common packet channel (CPCH) data coding scheme is used. And when the additional information is mapped to a TFCI field of the power control preamble, a TFCI coding scheme is used.